Central London residential redevelopment
Located in the heart of the Soho regeneration area, this 8 storey building is under redevelopment into a new residential complex, with restaurant and retail space at ground and basement level. The build consists of demolishing and rebuilding the top 3 levels and extending upwards a further level. The remaining levels in the complex have been redesigned.
Designs were supplied by RDG for a 17.5m x 50m temporary roof to provide protection from weather conditions. In some areas the temporary roof stands 12m higher than the last tie due to the demolition of the top 3 levels. Stability above the last tie location is maintained by the use of ledger bracing. Due to the different height required for the re-build, the roof was designed at 2 heights to assist with the stability and reduce labour and material costs.
Horizontal loads on the higher roof are managed by fixing into the neighbouring properties gable. Achieving stability of the lower roof was not possible by tying into the façade, as the rear light well elevation is approximately 5m from the building. The solution was to span across from the independent into the building and fix to the remaining steel columns on the 4th level. From the 5th level up, stability was managed by spanning through to the external scaffold and tying the structure together.
A façade scaffold was erected to all 4 elevations providing support to the temporary roof. The rear elevation required beams to span over the party wall roof. 1280mm ASTERIX HD beams were used, reducing labour and material costs as a large number of X Beams would have been needed to manage the loads from the temporary roof.
The large support loads were managed by steel spreader beams, designed to the required bearing pressure provided by the party wall engineer. These beams were sourced and delivered by RDG.
The 3 remaining elevations were designed in accordance with local authority pavement licenses and incorporated fans to provide protection to pedestrians below. Due to the close proximity of the road, the protection fans were positioned 5.5m above road level to provide clearance for large vehicles. A 10.00 kN/m2 gantry was constructed which cantilevered over the road meeting the clearance requirements. A lifting beam and goods/passenger hoist were also required.
All corners of the scaffold are wing braced and beams span at lower levels to tie the elevations together and give the structure stability.